From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752879Ab2DCH7Z (ORCPT ); Tue, 3 Apr 2012 03:59:25 -0400 Received: from mail-wi0-f172.google.com ([209.85.212.172]:62534 "EHLO mail-wi0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751239Ab2DCH7X (ORCPT ); Tue, 3 Apr 2012 03:59:23 -0400 Message-ID: <4F7AADD7.5070802@suse.cz> Date: Tue, 03 Apr 2012 09:59:19 +0200 From: Jiri Slaby User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120331 Thunderbird/13.0a2 MIME-Version: 1.0 To: Heiko Carstens CC: gregkh@linuxfoundation.org, alan@linux.intel.com, linux-kernel@vger.kernel.org, jirislaby@gmail.com, Martin Schwidefsky , linux390@de.ibm.com, linux-s390@vger.kernel.org Subject: Re: [PATCH 25/69] TTY: con3215, remove tasklet for tty_wakeup References: <1333367693-3244-1-git-send-email-jslaby@suse.cz> <1333367693-3244-26-git-send-email-jslaby@suse.cz> <20120403054241.GA2700@osiris.boeblingen.de.ibm.com> In-Reply-To: <20120403054241.GA2700@osiris.boeblingen.de.ibm.com> X-Enigmail-Version: 1.4 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/03/2012 07:42 AM, Heiko Carstens wrote: > On Mon, Apr 02, 2012 at 01:54:09PM +0200, Jiri Slaby wrote: >> tty_wakeup is safe to be called from all contexts. No need to schedule >> a tasklet for that. Let us call it directly like in other drivers. >> >> And delete the tasklet completely. > > Your patch actually reverts Martin's recent commit 656d912537 > "[S390] 3215 deadlock with tty_wakeup". > I'm quite sure the reason for the deadlock still exists. > Unfortunately the commit doesn't contain the call chain that > led to fix. Ok, I would really appreciate the trace. If this is really an issue, we should provide a helper in the TTY layer like tty_schedule_wakeup. thanks, -- js suse labs